Learning Resource Type

Classroom Resource

Making Math Matter: Adding & Subtracting Decimals

Subject Area

Mathematics

Grade(s)

5

Overview

In this video, teachers will learn classroom strategies for teaching decimal addition and subtraction in this professional development video from Making Math Matter.

    Mathematics (2019) Grade(s): 5

    MA19.5.3

    Using models and quantitative reasoning, explain that in a multi-digit number, including decimals, a digit in any place represents ten times what it represents in the place to its right and $\frac{1}{10}$ of what it represents in the place to its left.

    Unpacked Content

    UP:MA19.5.3

    Vocabulary

    • Digit
    • Decimal
    • Decimal point
    • Thousandths
    • Hundredths
    • Tenths
    • Base-ten
    • Expanded form
    • Place value
    • Power of 10
    • Factor
    • Base
    • Exponent
    • Product

    Knowledge

    Students know:
    • Each place value position represents 10 times what it represents in the place to its right.
      Example: In 433, the underlined 3 represents 3 tens and has a value of 30 which is ten times the value of the 3 ones to its right.
    • Place value understanding is extended to apply reasoning that a place value position represents 1/10 of what it represents in the place value to its left.
      Example: In 433, the underlined 3 represents 3 ones and has a value of 3 which is one-tenth of the value of the 3 tens or 30 to its left.
    • A given number multiplied by a power of 10 shifts the digits in the given number one place value greater (to the left) for each factor of 10.-A given number divided by a power of 10 shifts the digits in the given number one-tenth of the value (to the right) for each factor of 10.

    Skills

    Students are able to:
    • Reason and explain the relationship between two successive place values.
    • Explain patterns of zeros of the product when multiplying by powers of 10.
    • Explain patterns in placement of decimals when multiplying or dividing by power of 10.
    • Write powers of 10 using exponential notation.

    Understanding

    Students understand that:
    • The relationship of adjacent places values in the base ten system extend beyond whole numbers to decimal values.
    • Multiplying or dividing by a power of 10 shifts the digits in a whole number or decimal that many places to the left or right respectively.
    Mathematics (2019) Grade(s): 5

    MA19.5.4

    Read, write, and compare decimals to thousandths.

    Unpacked Content

    UP:MA19.5.4

    Vocabulary

    • Compare
    • Decimal
    • Thousandths
    • Hundredths
    • Tenths
    • Symbol
    • Greater than
    • Less than
    • Equal
    • Place value strategy
    • Expanded form
    • Expanded notation

    Knowledge

    Students know:
    • How to read and write whole numbers in standard form, word form, and expanded form.
    • How to compare two whole numbers using place value understanding.
    • Prior place value understanding with whole numbers is extended and applied to decimal values.
    • Recognize and model decimal place value using visual representations to compare.

    Skills

    Students are able to:
    • Read and write decimal values in word form, standard form, and expanded form.
    • Compare decimals to thousandths using , or = .

    Understanding

    Students understand that:
    • the adjacent place value relationship in the base ten system extends to decimals and is used to write decimals in expanded form and compare decimals.
    Mathematics (2019) Grade(s): 5

    MA19.5.8

    Add, subtract, multiply, and divide decimals to hundredths using strategies based on place value, properties of operations, and/or the relationships between addition/subtraction and multiplication/division; relate the strategy to a written method, and explain the reasoning used.

    Unpacked Content

    UP:MA19.5.8

    Vocabulary

    • Decimal
    • Tenths
    • Hundredths
    • Place value

    Knowledge

    Students know:
    • Strategies based on place value understanding, properties, and relationship between operations to find the sum, difference, product, and quotient of whole numbers.
    • How to write decimal notation for fractions with denominators of 10 or 100.
    • Use estimation strategies to assess reasonableness of answers.

    Skills

    Students are able to:
    • Use concrete models, drawings, and strategies to add, subtract, multiply, and divide decimals.
    • Relate strategies for operations with decimals to a written method and explain reasoning used.
    • Solve real-world context problems involving decimals.

    Understanding

    Students understand that:
    Problems involving operations with decimals
    • Can be solved using a variety of strategies based on place value, properties of operations, or the relationship between the operations.
    • Can be illustrated using concrete models or drawings.
    Link to Resource

    CR Resource Type

    Audio/Video

    Resource Provider

    PBS
    Accessibility
    License

    License Type

    CUSTOM
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